Protective cover for a mirror



FIG. 1 is a front elevational view of the protective cover for a mirror showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a top thereof; and,

FIG. 6 is a bottom elevational view thereof. 

The ornamental design for a protective cover for a mirror, as shown and described. 